Vulnerability Report

CVE-2026-23557

Title: Xenstored DoS via XS_RESET_WATCHES Command

DoS

Proof Of Concept

No public PoC currently indexed for CVE-2026-23557.

CWE Category NVD-CWE-noinfo

Published Date May 19, 2026

Modified Date May 19, 2026

Exploit Status Not Found

Score 6.5 CVSS v

Exploit Probability (EPSS)

0.16%

Vulnerability Summary

CVE-2026-23557: Any guest can cause xenstored to crash by issuing a XS_RESET_WATCHES command within a transaction due to an assert() triggering. In case xenstored was built with NDEBUG #defined nothing bad will happen, as assert() is doing nothing in this case. Note that the default is not to define NDEBUG for xenstored builds even in release builds of Xen.

Impacted Vendors

xensource_inc 1

xen 1

Reference Links

https://xenbits.xenproject.org/xsa/advisory-484.html http://www.openwall.com/lists/oss-security/2026/04/28/11 http://xenbits.xen.org/xsa/advisory-484.html

CVSS v3.1

Source Entity 134c704f-9b21-4f2e-91b3-4a467353bcc0

Severity MEDIUM

6.5

Attack Vector

LOCAL

Complexity

LOW

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

CHANGED

RAW VECTOR CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-23557 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

May 19, 2026 MODIFIED

Vulnerability data updated via NVD.

May 19, 2026 MODIFIED

Vulnerability data updated via NVD.

May 19, 2026 MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector LOCAL

Complexity LOW

Privileges N/A

Interaction NONE

CVSS Vector String


                                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

Affected Stack

No specific products linked.